Blender 2.8 Texture Painting weird brush behaivior
I found a workaround for this issue. While playing around with some settings i figured out that this is only when i activate symmetrie. However if i turn of the symmetrie, the lines are solid again.


Now the workaround is to draw like that with symmetrie on, so you have your drawing applied and its mirrored even with the weird brush and then you turn off symmetrie, increase the radius of the brush a little bit and draw on top of the weird lines. Its a bit extra work, but the best solution i found so far.